Steam turbine



Dec. 30, 1930.

K. RDER STEAM TURBINE Filed Dec. 16, 1927 Patented ec. 30, 193() Kan-L nonna, or nan'ovsn, GERMANY STEAM TUEBINE Application filed December 16,1927, Serial No. 240,506, and in German-y December 18, 19,26.

My invention relates to steam turbines. There are turbines in Awhich the introduction of the driving medium through the bore of the'shaft presentsy .particular advantages. Suchan arrangement is,-for instance, suitable for turbines with two rotors which revolve in opposite directions. The supply of the live driving medium then takes place through the bores of one oi both of the rotors. rllie transmission of heat from the driving medium to the' rotor must then be taken into account,whicli doesnot only involve a loss of energy, but might be detrimental to those partsof the rotor Awhich must belubricated, such as the bearings and the pinion.

According to my invention the supply members for the driving medium are so designed that not'only a detrimental transmission of. heat is avoided, but that even the heat from the shaft maybe dissipated through its bore.

F or this purpose two concentric tubes are in- Y troduced into the bore of the shaft in such a manner that besides the central tubular portion of full circular cross-section two further spaces of annular cross-section are produced.

'The central circular portion serves for the supply ofthe driving medium, such as high pressure steam. The annular space which surrounds this center directly is filled with a heat insulating material or a bad conductor V of heat, such asl infusorial earth, and is put v in communication withthe outside by linel radial bores in the shaft. The outer annular chambervis for the length of the portion of the shaft ycooled by the forced oill supply, usually employed for the general lubrication of the engine,in such a manner that this outer annular chamber is constantlytraversed by oil under vpressure during the running of the turbine. Int-his way is effected not only a .vigorous discharge ofthe heat transferrer from the live driving medium in spite of the heat insulating substance, but the cooling of the bearing and the driving pinion is proy"iting' part of my specification, this drawing moted and the usual heat dissipation at the A showing the pertaining shaft and bearing portion in longitudinal central section.

' Referring to the drawing, a is one of the two parts of the shaft journaled in the supporting beaiings b and o, the latter being designed as thrust bearing. On the shaft is also provided a pinion l the place of which may also be taken by the carrier of the runner blades of a medium or low pressure turbine or the revolving portion of a dynamo. Through the interior c of the inner tube i is introduced the driving' medium, for instance, high-pressure steam. rlhe flange of the tube is separated from the shaft portion g to be kept cool, by a plate z, made of a bad lconductor of heat, for instance asbestoscement. The inner tube z' is sealed against the shaft@ by a stuffing box Z whose material is compressedbygland m. As packing material for the stuffing box Z is employed a re silient material which permits axial expansion of the tube 7l in relation to the shaft a.

he tube z' is surrounded by an outer tube 7c and the annular space a between the tubes 'i' and le is filled with a resilient heat insulating material suchy as powdered infusorial earth. rlhe annularspace g between the outer tubelc and the boring wall of the shaft section g to be kept cool is` at one end in communication with .the yforced oil system of the engine bore 0 and at the other end by bore pl in communication with the oil discharge system, so that this yannular Vspace q is effectively iiushed with cold oil. In this way not only the passage of heat from the steam into the body oftheshaft g Ais prevented, -but the heat dissipation from thejournals is also assisted so that the bearings may be sub- ]ectedto a higherl load.y The outer tube /c is sealed against the shaft t by a'stuiiing box 0 which also permits of axial motion vbetween the ltwo parts. The annular spaces left between the end of tube 7c and the shoulder t ofstuffing boxl is` preferablylin communication with the outside byfinebores x in the shaft in order to provide an outlet for any leakage fluid, either steam or oil.

The flow of the oil through the annular space g is preferably assisted by making the diameter of the shaft at the place where the gli a oil inlet V0 is located smaller than at the place has Vthe tendency to fling the oil.

VariousY modifications and changes may 4be made'vvithout departing from the spirit and the scope of the invention, and li .de-sire, therefore, only such limitations shall kloe Y placed thereon as4 are imposed Llby fthevr prior art. n .Y i,

' I claiinas-,niy invention p n V1. A hollow rotatable shaft serving as a hot-,pressure fluid conduit 'and `having central hot pressure fluid conducting pipe cf suitable diameter ato form an annular 'chamf Y berbetween the "pipe andthe inner shaft i Wall, torpreventheat from flowing4 from the Vfio ' said' oil supply.

pipe to the shaft, 'and means .for circulating: cooling fluid through said chamber;

2Q AholloW rotatable' shaft serving las a steam .conduit yand `havinga central steam conducting pipeandia pipe surrounding said central pipe, said v'pipe-s formingfftvvoxccncentric .annular vchambers surrounding the central port-ion of said steam pipe, heat insulating material disposedlintlie inner of said annular chambers, means for supplying oil and .means for putting, the'router of sai'd 33Av hollow rotatableshaftserving as va steam conduit andhaving a centrall steam conducting vpipe and afpipe surrounding said central pi pe,lsaidpipes forming two concentric annular Ychain-bers surrounding annular Chambers in communication With Y `mer/,ses

said central pipe, said pipes forming tivo concentric annular` chambers surrounding the central portion of said steam pipe, heatinsulating materialdisposed inthe VVinner of said annular chambers, means for supplying oil, saidl shaft having a bore forco-nnecting said cuterfcliamber `vvitli'the; oil supply and afbore for dischargiugthe oil from said chamber, theniouth of said second bore bee ing located agreater radialdistance from thelshaf-t center than the mouth of thejoil supply bore for further-ing tlie'oil circula tion lthrough said chamber. Y

Y 6. A hollow rotatableshaft serving asa steam conduitY andlhaving' acentrarl steam conducting pipe and a pipe surroundingsaid central pipe, said pipes forming two con- 'Y centric annular chambers surrounding the central portion'of said steam pipe, heat insulating material disposed in the inner of said annular chambers, means Y,for supplying oil, said shaft having a lhere for connectingI said outer chamber with the oil-supply and a bore for discliarging'the oil from said chamber, the mouthvr ofvs'aid'secondbore being located a. greater radial 'distance fromv the shaft center than rthe mouth lof the oil supply bore, said oil supply bore deviating from 'the Vradi al direc-tion towards -t'lie 'direction' of 'shaft'rcta-tionfsaid oil discharge here Y deviating in the opposite directioni-for Vfurthering the" oil circulation vthrough said chamber.l Y

. In testimony -vvhereof I afIiXk mysignature.

'y [KARL "BoD-2R'.

' thecentral ,portion of sai'dsteainpipe, :heat v Y steam. conduit andV hayingfV4 .a central steamV 'chamber-.c

f steam conduit land having -a centralr steam] vinsulating material disposed Yin the Vinner of said annular chambers,y means :for supplying oiland-means for putting the outer .of saidv annularfchambers iii `communicati'on 'with said ,oilff supply, and a leakage chamber adapted (to receive"leakagefluid from both" annular chambers. and meansgfor draining said/'leakage chamber to the outside.V

4. .A V,hollow1rotatable-shaft servingv as ^Va conducting lpipe anda v,pipe surrounding said centralpipepsaid pipes formingtwo concentric an-riul arVV ch amberssurroun din -the central portion ofsaid steam pipe, ,heatinsulatingqmaterial disposed" in the inner of said annulary chambers, means for supplying oil,saidshaftahaving a bore for vconnecting said -outerfchamhfer -W'ith the oil supplyJ-andflj a bore'foradischarging they oil fro'misaid `5,.y lA hollow.V Yrotatab'le shaftiservi-ng as a conducting pipe `and la pipe surrounding lili) 

